Journal ArticleDOI
Electrical bioimpedance readings increase with higher pressure applied to the measuring probe.
C. A. González-Correa,C. A. González-Correa,Brian H. Brown,Rod Smallwood,Dawn Walker,K D Bardhan +5 more
TLDR
It is found that, with increasing pressure, the resistivity readings increase in a consistent way up to 80% and it is hypothesize that these changes may be mainly associated with the squeezing of water from the extracellular space.Abstract:
Electrical bioimpedance spectroscopy (EBIS) is a technique that uses a probe to calculate the transfer impedance from tissues. This transfer impedance can give information about the normal or pathological condition of the tissue. To take readings, pressure has to be applied to the probe in order to get a good contact between the electrodes and the tissue. We have been using EBIS to investigate the early diagnosis of dysplasia and cancer in the human cervix, oesophagus and bladder. We have found that, with increasing pressure (range used here was approximately 1 kPa to approximately 50 kPa), the resistivity readings increase in a consistent way up to 80%. In this paper, we show how this is a case in three different tissue types (oesophageal, gastric and vesical samples). These increases can be higher than those associated with the pathological changes that we are investigating (non-inflamed columnar tissue, for instance, shows values 50% higher than dysplastic columnar tissue). Finite-element modelling was also used to investigate the effect of volume reduction in the connective tissue or stroma. This simulation suggests no strong correlation between reduction of this structure and increase in resistivity. We hypothesize therefore that these changes may be mainly associated with the squeezing of water from the extracellular space. Finally, as pressure is difficult to control by hand, we raise the issue of the necessity of considering this variable when making EIS measurements.read more
Citations
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Journal ArticleDOI
Subepidermal moisture (SEM) and bioimpedance: a literature review of a novel method for early detection of pressure-induced tissue damage (pressure ulcers).
TL;DR: The SEM Scanner, a handheld medical device, offers an objective and reliable method for the assessment of local bioimpedance, and therefore, assessment of tissue damage before signs become visible to the unaided eye.
Journal ArticleDOI
Bioimpedance of soft tissue under compression.
TL;DR: Using a Cole-Cole model, nonlinear compositional changes in extracellular and intracellular makeup; related to a loss of fluid from the tissue, are identified during compression, possibly indicating two distinct phases of mechanical change in the tissue during compression.
Journal ArticleDOI
Genetic and least squares algorithms for estimating spectral EIS parameters of prostatic tissues.
Ryan J. Halter,Alex Hartov,Alex Hartov,Keith D. Paulsen,Keith D. Paulsen,Alan R. Schned,John A. Heaney +6 more
TL;DR: No significant differences were observed between CaP and BPH for the spectral parameters Deltarho and f(c); this is especially important since current prostate cancer screening methods do not reliably differentiate between these two tissue types.
Patent
Sem scanner sensing apparatus, system and methodology for early detection of ulcers
Majid Sarrafzadeh,William J. Kaiser,Alireza Mehrnia,Barbara Bates-Jensen,Frank Wang,Michael Flesch,Joseph Boystak,Yeung Lam +7 more
TL;DR: In this article, a handheld, conforming capacitive sensing apparatus configured to measure Sub-Epidermal Moisture (SEM) as a mean to detect and monitor the formation of pressure ulcers is presented.
Journal ArticleDOI
Elastic scattering spectroscopy for detection of cancer risk in Barrett’s esophagus: experimental and clinical validation of error removal by orthogonal subtraction for increasing accuracy
Ying Zhu,Tom Fearn,GD Mackenzie,Benjamin R. Clark,Jason M. Dunn,Irving J. Bigio,Stephen G. Bown,Laurence Lovat +7 more
TL;DR: EROS works well as an effective pretreatment for Barrett's in vivo data by identifying measurement variability and ameliorating its effect, and reduces the complexity and increases the accuracy and interpretability of the model for classification and detection of cancer risk in Barrett's esophagus.
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Journal ArticleDOI
Electrical impedance spectroscopy and the diagnosis of bladder pathology: a pilot study.
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